sanford



@uiten gisten gutem @frn Letters Patent No. 79,012, dated June 16, 1868.

IMPROVEMENT IN AUGERS.

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lO ALL WHOM I'lV MAY CONGEBN:

Beit known that I, N. C. SANFORD, of Meriden, in the county of New Haven, and State of Connecticut, have inventeda neimand improved Auger and I (lo hereby declare that the following 4is a full, clear, and exact description thereof, which will enable those skilled in, theart to make anduse the same, reference being had to the accompanying drawings, formingpart of this specification, in whic h- Figure 1 is a side-'view of my vimproved auger; Figure 2 is a. bottom v iew of the same. v i

Figure 3 is an enlargeddetail side view, showing ,the formation of the 'cutting-lips in a di'ereut position from that of g. 1.

Similar letters of reference indicate corresponding parts.

This invention consists in forming an auger wit-h two or more cutting-lips, commencing from the first or usual cnttingglip, andi-passing around the last turn ortwist ofthe helical part ofthe auger, and each successive lip being at a greater distance from the axial centro of the auger ythan the preceding, and in a different horizontal plane, whereby the paths of the several lips aredilerent and distinct, and the auger may be operated more easily. i

The lips are forpied with a vertical cutting-edge, as shown at a 6 c, springing from the lower 4edge of the twist, A, and being a vertcalcontinuation of the sharpened horizontal edges UZ ef, as shown.,

These latter edges are rectilinear, or they may be slightly concave or convex, without materially acfectiug the boringqualities of the tool.

My invention may be applied` to double-twist angers, as will be obvious.

The txristA is formed in the usual way, and the several lips are forned by the process known as swaging I claim as new, and desire to secureby Letters Patent- Two or more cutting-lips, a b c, of dilerent radial distance from the axial centrefof the auger, and in d ifferent horizontal planes, all constructed to operate substantially in the manner and for the purpose as -set-forth.

n. o. SANFORD.

Witnesses:

JOHN IvEs, ANDW G. LOWEREE. 

